import { HttpClient, HttpHeaders } from '@angular/common/http';
import { Injectable } from '@angular/core';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/map';
import { Task } from '../../pages/tasklist/task';

/*
  Generated class for the HttpDataProvider provider.

  See https://angular.io/guide/dependency-injection for more info on providers
  and Angular DI.
*/
@Injectable()
export class HttpDataProvider {

  private readonly baseUrl: string = 'https://api2.bmob.cn/1';
  private readonly httpOptions : Object = {
    headers : new HttpHeaders({
      'X-Bmob-Application-Id':'b1d2ffae56b7da820c506d80a0ef7b8a',
      'X-Bmob-REST-API-Key':'f5c19da5ba615c1b61fd28d3f65b2892',
      'Content-Type':'application/json',
    })
  };

  constructor(public http: HttpClient) {
    console.log('获取HTTP数据服务加载');
  }

  /**
   * 获取待办事项列表
   * @returns {Observable<Task[]>}    代办事项列表数据集合
   */
  getTaskList(): Observable<Task[]>{
    return this.http.get<Task[]>(`${this.baseUrl}/classes/ToDoList`,this.httpOptions).map(data => data["results"]);
  }

  /**
   * 获取指定待办事项
   * @param objectId 
   * @returns {Observable<Task>}    代办事项
   */
  getTask(objectId: string):Observable<Task>{
    return this.http.get<Task>(`${this.baseUrl}/classes/ToDoList/${objectId}`,this.httpOptions);
  
  };

  /**
   * 新增待办事项
   * @param task 
   * @returns {Observable<Task>} 响应结果
   */
  addTask(task : Task): Observable<Task>{
      let _task = {title: task.title, status: task.status, description:
      task.description};
      return this.http.post<Task>(`${this.baseUrl}/classes/ToDoList/`,
      _task,this.httpOptions);
  }

  /**
   * 更新指定代办事项
   *  @param task
   * @returns {Observable<Task>} 响应结果
   * */
  updateTask(task : Task): Observable<Task>{
    let _task = {title: task.title, status: task.status, description:
    task.description};
    return this.http.put<Task>(`${this.baseUrl}/classes/ToDoList/${task.objectId}`,
    _task,this.httpOptions);
  }

  /**
   * 删除指定代办事项
   * @param task 
   * @returns {Observable<Task>}   响应结果
   */
  deleteTask(task : Task):Observable<{}>{
    return this.http.delete(`${this.baseUrl}/classes/ToDoList/${task.objectId}`,
    this.httpOptions);
  }

}
